Predicting Combustion Behaviors of the Emitted Gas during Thermal Runaway of Lithium-Ion Batteries

Electric cars contribute to the de-carbonization of the transport sector and their massive deployment is foreseen. In this context, the battery industry strives for ever improved technologies, both in terms of performance and safety. For the latter, the avoidance of the thermal runaway (TR) of batteries is of prime importance since it  has caused a number of accidents around the globe. Indeed, TR  may lead to combustion and explosion, presenting dangers to human lives. Recently, a trade-off has been observed since the thermal stability of batteries is found to decrease for new battery materials allowing for higher energy density.
During the process of battery thermal runaway, various gaseous components are formed by both exothermic decomposition reactions between battery materials and the evaporation of liquid electrolyte. These emitted gases, usually flammable and toxic, are responsible for the drastic events such as battery cell rupture, venting, combustion, explosion, and flames. During different phases of TR, the risk and severity of combustion may vary, depending on the composition of the gas mixture and the gas-phase reactions under the corresponding temperature and pressure. However, the relation between the gas-phase combustion and the thermal runaway in condensed phases are still unclear. This PhD research aims to understand such relations and develop a multi-physics kinetic model with validation based on experiments to predict the entire process of emitted gas combustion, from their formation in the solid/liquid phase to their combustion behaviors in the gas phase. The PhD student will address many scientific questions around combustion during thermal runaway, e.g., when, where, and how combustion initiates, propagates, and affects the progress of thermal runaway. He/she will gain a solid experience in lithium-ion battery, combustion, and chemical kinetics through the multi-physics modeling activities.

Keywords: Thermal Runaway, Lithium-Ion Battery, Kinetic Modeling, Combustion, Auto-Ignition, Flame

• Academic supervisor    Prof. Laurent CATOIRE ENSTA Paris, ORCID 0000-0002-7484-6071
• Doctoral School    ED626 –Institut Polytechnique de Paris
• IFPEN supervisor    Dr. Boyang XU, ORCID 0000-0003-0257-2064
• PhD location    IFPEN, Rueil-Malmaison, France 
• Duration and start date    3 years, starting time flexible throughout year 2024
• Employer    SAFT, Bordeaux, France
• Coordinator Guillaume Gimenez, guillaume.gimenez@saft.com 
• Academic requirements    University Master degree in chemical engineering, physical chemistry, electrochemistry, or materials engineering
• Language requirements    Fluency in English (level B2 CEFR), willingness to learn French
• Other requirements    Modeling. Programming (Python). Knowledge in chemical kinetics is a plus.

To apply, please send your cover letter and CV to the IFPEN supervisor indicated below.